María Luisa Penne Rullan de Castillo (11 September 1913 – 6 October 2005), born in Ponce, Puerto Rico, was a painter, artist, and educator who taught and influenced the work of well-known artists such as Noemí Ruiz, Jaime Carrero, Rafael Rivera Garcia, and printmaker Susanna Herrero among others.

After returning to Puerto Rico, Mrs. Castillo or "la teacher" - as she was known to her disciples - began to work for the empowerment of women in the art world, a field traditionally reserved for male members of society. She firmly believed in the importance of education as a means to achieve such empowerment. Therefore, she decided to get involved in the field of art education.